10,11-Dihydro-5-methyldibenzo[a,d]cyclohepten-5,10-imine, also known as MK-801 is a potent anticonvulsant and is the subject of U.S. Pat. No. 4,399,141 by Anderson et al.
The 11-exo-hydroxy derivative of MK-801 has been shown to be a major mammalian metabolite of MK-801 and both compounds have been shown to be N-methyl-D-aspartate (NMDA) antagonists useful in the treatment of neurodegenerative diseases such as Alzheimer's disease and related neurological disorders as described by Britcher et al., in European patent publication No. 0264183.
The synthetic route disclosed in the prior art for the synthesis of 11-exo-hydroxy-MK-801 is very inefficient with an overall yield of about 11% to racemic product. ##STR2##
Now with present invention, there is provided a new process for preparing racemic 11-exo-hydroxy-MK-801 in about 50% overall yield.